Comparison of two microkeratome systems

Area of Science:

• Ophthalmology
• Biomedical Engineering
• Surgical Technology

Background:

• Microkeratomes are crucial for refractive surgeries like automated lamellar keratoplasty and LASIK.
• Reported visual and refractive complications necessitate understanding microkeratome performance.
• Comparing microkeratome performance can elucidate mechanisms behind refractive surgery complications.

Purpose of the Study:

• To compare the performance of two microkeratomes: Chiron Automated Corneal Shaper and Eye Technology's MicroPrecision.
• To evaluate their ability to resect corneal lamellae for refractive surgery.
• To gain insights into complications following lamellar refractive procedures.

Main Methods:

• Automated lamellar keratoplasty was simulated on an eyebank eye model to correct 10.00 D myopia.
• Key metrics included wet/fixed diameters, excised tissue thickness, and scanning electron microscopy.
• Ultrasonic pachymetry and a mechanical compression gauge assessed tissue thickness.

Main Results:

• The Chiron automated corneal shaper produced blade chatter, smaller excisions, and variable tissue thickness.
• The MicroPrecision microkeratome yielded smoother resections without blade marks.
• MicroPrecision excisions more closely matched intended diameters and thicknesses.

Conclusions:

• Microkeratomes differ in their corneal tissue resection morphology.
• Instrument design, excision mechanics, blade oscillation, and surgical technique influence lamellar keratotomy outcomes.
• Understanding these differences is key to improving refractive surgery safety and efficacy.